Re: [PATCH] ASoC: soc-core: Create device_link to ensure correct suspend order

[Richard Fitzgerald <rf@opensource.cirrus.com>]

On 02/06/2026 2:46 pm, Mark Brown wrote:
> On Tue, Jun 02, 2026 at 02:34:53PM +0100, Richard Fitzgerald wrote:
>> On 02/06/2026 2:31 pm, Mark Brown wrote:
> 
>>> Do we still have devices registering separate components with the same
>>> device for DMA and DAI operations?  They'd end up duplicating the links
>>> here.
> 
>> Ok, weird, but I agree it's possible for one driver to register multiple
>> components. I'll make a V2 that skips the device link if the component
>> dev is the same as the card dev.
> 
> That wouldn't avoid the issue I think?  The card is a separate device,
> but the DMA and DAI are two devices registered separately.  This used to
> be because we had completely separate driver types for DMA and DAI,
> prior to the component refactoring.  A simple move to component would
> keep two separate components, this could be refactored into a single
> component but that'd need to actually happen and I'm not sure we did
> that for everything.  I was wondering if you'd checked already, sounds
> like no?

Oh, you mean two components with the same dev, so that the
device_link_add() gets called for the same (card,component) devices
multiple times?

I tested multiple calls for the same device pair, and it's ok.
This also covers the case where ASoC core now creates this device_link
and the codec driver also creates the same device_link between the
card and itself (hdac_hdmi does this).

 From the kernel doc for device_link_add():

"if a device link between the given @consumer and @supplier pair
  exists already when this function is called for them, the existing link
  will be returned"